Is it actually possible to live a holy life in a holy world and never do anything which is morally wrong? Remember that there are “sins of omission” as well as “sins of commission”. As well as “the evil we have done” there can be “the good we have left undone.”
Anyone, then, who knows the good he ought to do and doesn’t do it, sins. (James 4:17)
God calls us to love our neighbours. There can be time when loving our neighbour demands action and failing to act would be the wrong thing to do.

Many ethical theories and some Christian philosophers argue that there are situations when inaction is not an acceptable option and we need to choose between “the lesser of two evils.” This principle is used to justify actions which are in themselves wrong but are the preferred “lesser evil” in the circumstances. They also talk of some actions as a “necessary evil” which are acceptable because they lead to a greater good. So some will say “the end justifies the means. This is applied to various situations including:
1. Divorce, which although undesirable is preferable to continued intolerable suffering
2. Telling a lie in order to save a life (are there any Jews hiding in your attic?)
3. Abortion to save the mother’s life
4. Euthanasia to end intolerable suffering of an incurable condition
5. Stem Cell research – experimentation with embryo tissue to create cures
6. Medical experimentation on animals
7. God’s command to wipe out the evil tribes in Canaan to prevent future harm to Israel
8. Going to war and even murder in war, defending those who cannot defend themselves
9. Taking up arms against an unjust state (anti-Apartheid in South Africa)

But is this “lesser of two evils” approach acceptable to Christians? As an example let us consider the principles of pacifism as they relate to 7, 8 and 9 above. During the Reformation our Anabaptist forebears emphasised non-violence and peace-making, insisting that violence is never justified. Consequently Christians must never become soldiers or go to war. They based this understanding on Jesus in the Sermon on the Mount in Matthew 5:38-48.
“But I tell you, Do not resist an evil person.” (v 39)
“If someone strikes you on the right cheek, turn to him the other also.” (v 39)
“But I tell you: Love your enemies and pray for those who persecute you.” (v 44)
In 3rd Century, Tertullian wrote, “In disarming Peter, Jesus disarmed every soldier.” He was referring to Matthew 26 51 With that, one of Jesus’ companions reached for his sword, drew it out and struck the servant of the high priest, cutting off his ear. 52 “Put your sword back in its place,” Jesus said to him, “for all who draw the sword will die by the sword.”
Paul also wrote in Romans 12 17 Do not repay anyone evil for evil. 19 Do not take revenge.
Against the non-violent understanding, Reformer John Calvin countered: Christians are allowed to use force “out of love for thy neighbour.” Roman Catholics argued that within the limits of Just War theory, violence in war can be a necessary evil. The State is allowed and obliged to use violence to defend its people.
For (the one in authority) is God’s servant to do you good. But if you do wrong, be afraid, for he does not bear the sword for nothing. He is God’s servant, an agent of wrath to bring punishment on the wrongdoer. (Romans 13:4)

So can a lesser evil argument ever justify violence? Even murder? Causing suffering ? How about lying? See also my sermon on obeying the State in Romans 13 http://pbthomas.com/blog/?p=184